The present invention relates to a method for operating electronically controlled machines, in particular, and to a control device for operating controlled machines.
The method of the invention and the apparatus of the invention are described with respect to packaging machines, textile machines, and the like. However, it will be noted that the method and the apparatus can also be used for other kinds of machines, such as printing presses or automation systems. The invention is moreover suitable for electrically, hydraulically, or pneumatically controlled machines as well.
Such methods for operating machines have long been known in the prior art. Such controllers for instance make it possible to guide the motion of movable machine elements of these machines. These machine elements are controlled using a motion profile specific to the motion. In the prior art, it is known to describe suitable motion profiles or cam disks as a rigid path of motion that is traversed cyclically. For instance, DIN 21 43 (in which the cam disk is described as a rigid path of motion that is cyclically traversed) is based on such controllers.
In the method from the prior art, however, the course of the cam disk is merely cyclical and is fixedly defined from beginning to end. Any change in the path of motion is therefore possible only by manually switching to a different cam disk.
European Patent Disclosure EP 1 220 069 B1 describes a method for setting up flexible cam disk functions by way of a control or applications program. A cam disk function that describes a motion of a machine element is described in portions; successive motion portions are defined by segments or points, and between such motion portions, interpolation is done in accordance with a predeterminable interpolation rule. Commands for predetermining and inserting points, segments, and interpolation rules for the transit time are provided, and the cam disk function is set up by way of commands in the transit time system of a machine controller. At the same time, in EP 1 220 069 B1, a cyclical or rigid motion sequence is generated, and in particular no jumps in individual motion steps of the motion sequence are possible. The individual paths of motion are moreover only limitedly changeable.